There is uncertainty here. The South Island Loess Project was a long time ago and only fragmentary records have survived. Here we try to pull together some useful material and indicate where the findings and the aims of the SILC might still be relevant and useful. In 1973 the INQUA Congress was in New Zealand and as part of the preparations for this Congress the New Zealand Soil Bureau set out to examine the loess deposits in the South Island. Now the NZ loess is interesting and fairly widespread but it definitely lacks signals to facilitate stratigraphic examinations, and there are not many good exposures. A coring progamme was undertaken to provide a set of samples on which careful stratigraphic examinations could be carried out- possibly using slightly unconventional methods. We think that Mike Leamy initiated this coring programme and that Ken Birrell had a major involvement; the start date is believed to be 1971. Eight sites were chosen:
1. Barry's Bay S94 234277 dated 051071
1A Barrhill S82 305406
2. Claremont S111 683496
3. Darling's Property S111 766479
4. Awamoko S127 578132
5. Romahapa S179 518132
6. Pukerau S170 976415
7. Stewart's Claim S161 921619
Sites 2 and 3 were fairly close to Timaru, and sites 5,6 and 7 not too far from Dunedin/Gore. Site 4 was south of the Waitaki River, quite near to Oamaru. Sites 1 and 1A were the most northerly, in the vicinity of Christchurch.
Cyril W.Childs 1975 Distributions of elements in two New Zealand Quaternary Loess columns. in Quaternary Studies: Selected Papers from 9th INQUA Congress Christchurch New Zealand 2-10 December 1973. ed. R.P.Suggate and M.M.Cresswell, pp. 95 - 99.
1. Barry's Bay S94 234277 dated 051071
1A Barrhill S82 305406
2. Claremont S111 683496
3. Darling's Property S111 766479
4. Awamoko S127 578132
5. Romahapa S179 518132
6. Pukerau S170 976415
7. Stewart's Claim S161 921619
Sites 2 and 3 were fairly close to Timaru, and sites 5,6 and 7 not too far from Dunedin/Gore. Site 4 was south of the Waitaki River, quite near to Oamaru. Sites 1 and 1A were the most northerly, in the vicinity of Christchurch.
Cyril W.Childs 1975 Distributions of elements in two New Zealand Quaternary Loess columns. in Quaternary Studies: Selected Papers from 9th INQUA Congress Christchurch New Zealand 2-10 December 1973. ed. R.P.Suggate and M.M.Cresswell, pp. 95 - 99.
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| Element distributions for K, Ca and Ti in the Claremont no.1 column. Stratigraphic layer numbers and morphological horizon designations are given at the top of the figure. The error bars represent estimates of the uncertainty in the values for each element. Note that the Claremont column is in the loess near Timaru. |
The loess at Claremont must be essentially the same as that exposed at Dashing Rocks- with those well developed fragipans on display. There does not seem to be any evidence in the Claremont results that fragipans are formed by movement of elements down through the soil system. Claremont suggests a physical or mechanical mechanism of fragipan formation.
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